With the maturity of the 3G technology and products, the deployment and service of 3G networks increase significantly throughout the world. As an advanced service with full characteristics of the 3G communication service, the mobile video phone service is becoming a reality with the arrival of the 3G service.
As communication, computer, voice and video encoding and decoding technology develop, the Video Phone (VP) develops rapidly. The VP integrates voice, image and data etc. for long distance transmission via communication lines, so that a person may hear the other party's voice and see the other party's image in communication between two places, thereby enhancing the reality, intimacy and on-site perception of communication. The VP is suitable for not only family life but also various fields of different industries, such as commercial activity, remote teaching, security monitoring, hospital nursing and medical diagnosis, thus the VP has wide market prospect.
The mobile video phone service based on video mobile terminal is a point-to-point communication service which may simultaneously utilize audio and video defined in the Universal Mobile Telecommunication System (UMTS), which may implement bidirectional real-time communication of audio and video between two video mobile terminals, or between a video mobile terminal and a video fixed terminal or between a video mobile terminal and a PC. In contrast with the conventional mobile phone service, the development of the mobile video phone service is a great challenge for system providers and mobile network operators due to the limit of bandwidth, cost, equipment and service.
At present, though large-scale commercial deployment of the VP service has not begun in a 3G network, the recognition and expectation for the mobile video phone service is very high, and the mobile video phone service will facilitate the development of 3G networks.
At present, a function of a video mobile terminal replacing its own voice or picture with a local audio or video file of the terminal in a communication process has been realized. By applying this function in communication between two or more parties, video mobile terminals participating in the communication may replace their voice and/or pictures with pre-stored audio and/or video media stream as needed and send the media stream to other terminals participating in the communication so that the other terminals may receive the replaced audio and/or video etc. multimedia information. In such an application, the replacing media stream is provided by the video mobile terminal originating the media stream replacing, so there are limitations such as limits on storage capacity and selectivity, etc. Operators are unable to launch a charge service for the application because the replacing process does not need the intervention of a server.